界面张力与乳状液稳定性试验研究

研究了乳状液的稳定性与界面张力的关系，探索了破乳剂浓度、乳状液温度及含水率对其稳定性的影响。结果表明，对于同一种乳状液，它的界面张力值降低越多就越不稳定；随着乳状液中破乳剂含量的增加，界面张力呈现先下降后上升的趋势；破乳剂的效果受油品性质、含水率的影响较大；对于同一种油品，存在具有最佳HLB值的破乳剂，使油水界面吸附量最大，界面张力值降至最低，乳化现象最不容易发生。     

石油磺酸盐与原油乳化影响因素研究

采用显微观测与乳状液析水率测定相结合的方法研究石油磺酸盐与原油乳化问题。通过正交实验,研究石油磺酸盐质量分数、油水体积比及振荡次数等因素对乳状液液滴结构及稳定性的影响。结果表明,油水体积比对乳状液液滴结构影响最大,随着油水体积比的增大,乳状液平均粒径和分散度先增大再减小。乳状液破乳前期,油水体积比对乳状液析水率的影响最大;乳状液破乳后期直至破乳结束,石油磺酸盐质量分数对乳状液析水率的影响最大;振荡次数对乳状液析水率的影响较小。     

泡沫复合驱原油乳状液稳定性影响因素研究

通过乳状液稳定性试验考察了泡沫复合驱原油乳状液稳定性。结果表明：单一的泡沫剂和聚合物对原油乳状液稳定性有较大的影响;两种驱油剂之间有明显的协同作用,复合驱油剂对原油乳状液稳定性的影响远远大于单一驱油剂的影响;其次,破乳温度、破乳剂用量及乳化强度对原油乳状液的稳定性也有明显的影响。     

不同结构破乳剂对原油及其酸碱组分表面膜的影响

 采用Langmuir-Blodgett(L-B)技术测定孤岛原油及其酸碱四组分表面膜膜压随水相破乳剂浓度的变化,考察了4种不同结构的破乳剂对原油及其酸碱四组分表面膜膜压的影响。结果表明,破乳剂对原油及其酸碱四组分的表面膜膜压降低程度与其结构和浓度有关。支链型破乳剂AE8025可以显著降低原油及其酸碱四组分的表面膜膜压,并随着破乳剂浓度的增加,表面膜膜压逐渐降低;其降低酸性分、碱性分和两性分表面膜膜压的程度大于对中性分的。与直链型破乳剂相比,支链型破乳剂降低孤岛原油及其酸碱组分表面膜膜压的能力更强,说明支链型破乳剂对原油及其组分乳状液中界面活性物质的顶替作用更强,破乳效果更优;当破乳剂浓度相同时,破乳剂对原油酸性分表面膜膜压的影响远大于其它3种组分的。     

疏水缔合聚合物驱体系中原油乳状液性质及破乳规律

采用瓶试法考察了原油组成及疏水缔合聚合物（Hydrophobically associating polymer, HAP）质量浓度对原油乳状液稳定性的影响,用油 水界面张力、界面电性、界面扩张流变、界面剪切黏度等多个参数表征了HAP驱采出液油 水界面性质的变化规律,用一系列酚胺树脂聚醚破乳剂对模拟采出液进行破乳。结果表明,原油中胶质和沥青质是影响原油乳状液稳定的重要因素;实验浓度范围内,随着HAP浓度升高,原油乳状液稳定性增强。HAP具有界面活性,吸附在油 水界面可降低界面能,利于乳化;HAP在界面上形成交联网状结构,提升了界面膜的扩张模量和剪切模量,同时增强了界面膜的负电性,利于稳定乳状液。环氧乙烷与环氧丙烷各占一半的酚胺树脂聚醚破乳剂与1%甲苯二异氰酸酯（TDI）交联后,5 min即可完全将原油乳状液破乳。     

浅论影响原油乳状液破乳的因素

从原油乳状液，破乳剂，外界破乳条件三个方面论述了原油乳状液稳定存在的原因及影响破乳的因素，并结合乳状液办面性质分析了好的破乳剂具备扩散吸附性好，润湿能力强，絮凝聚结能力强的性能及外界因素影响破乳的原理。     

含固体颗粒二元复合驱原油乳状液破乳研究

为了有效处理含固体颗粒的聚合物/表面活性剂二元复合驱原油乳状液油水分离困难的问题,采用界面张力仪和全功能稳定性分析仪考察了硅藻土、破乳剂、部分水解聚丙烯酰胺(HPAM)和石油磺酸盐表面活性剂对胜利海上原油二元复合驱采出液稳定性和油水界面性质的影响。结果表明,非离子破乳剂ECY-05和有机硅破乳剂589按质量比4∶1组成的复配破乳剂FP的破乳效果良好,随着FP加量增大,乳状液稳定性降低,油水界面张力减小,脱水率增加,FP加量为200 mg/L时,含固原油乳状液60 min脱水率为88%;随着HPAM、表面活性剂和硅藻土含量的增加,乳状液稳定性增加,脱水率降低;油水界面张力随着硅藻土加量的增大而增大,随表面活性剂浓度的增大而减小,HPAM对油水界面张力影响较小,三者的协同作用使得脱水率降低。     

环烷酸铁对老化原油破乳的影响及脱铁机理研究

考察了环烷酸铁对油水乳状液稳定性的影响并对老化油的脱铁机理进行了探讨。实验结果表明：随着乳状液中环烷酸铁含量的增加,乳状液中水滴粒径减小,脱水率降低,水中含油量增大,zeta电位负值增大,乳状液稳定性增强。将聚天冬氨酸与乙酸1:1复配,并分别添加50 mg/L的助剂HCl、NaCl及甲醇,均能提高破乳剂BSE-238对老化油的脱铁率和脱水率。利用偏光显微镜和电导滴定法对破乳脱铁机理进行了探讨,证明加入聚天冬氨酸和破乳剂BSE-238 均能促进液滴聚并,降低乳状液稳定性,且络合剂和油中的铁反应生成一种水溶性的离子络合物并随破乳脱水脱出铁,使水溶液电导率增加,电导率变化曲线与对脱铁的络合机理的推测吻合。     

聚醚破乳剂结构与压裂乳状液破乳效果的关系

以1,3-丙二醇、四乙烯五胺、聚酰胺-胺为起始剂合成了直链型、支链型及枝状聚醚破乳剂,采用瓶试法测定了这些破乳剂对模拟压裂乳状液的破乳效果,考察了破乳剂类型及分子结构对破乳效果的影响。结果表明,支链聚醚破乳剂的破乳效果优于直链聚醚破乳剂,且支化程度增加对破乳有利;以3.0代枝状聚酰胺-胺为起始剂的聚醚破乳剂破乳效果最好,当环氧乙烷与环氧丙烷的质量比(m(EO)/m(PO))为1/3、起始剂质量分数为0.5%时,制备的枝状聚醚破乳剂对模拟压裂乳状液7min即可完全破乳。     

一种研究和评价复合化学驱采出液破乳剂的方法

比较了一种常规破乳剂与一种专门研制的复合驱破乳剂在模拟化学复合驱条件下的动态界面张力、运用Gibbs公式求出每种乳破剂在油水界面的吸附量以及每个破乳剂分子在界面所占的平均面积,从而研究破乳剂分子在没水界面的吸附对界膜稳定性的影响。初步发现,易于在油水界面吸附的乳剂由于形成的界面膜稳定性差,使得乳状液易于破乳。这为破乳剂的研制与筛选提供了一种方法。     

不同结构破乳剂对原油乳状液的适用性研究

采用大庆油田采油四厂杏二中原油和污水,在室内配制原油乳状液,研究了不同结构破乳剂（SP169、BP169—21、AE9901、AR36、AP221、TA1031）及其浓度对不同矿化度原油乳状液的适用性。结果表明：AR36脱水速度最快、水色清、油水界面清晰,最大脱水率为88％,适用于大庆杏二中原油乳状液的脱水;AE9901的脱水率为729／6,SP169为70％,TA1031为64％,BP169-21为58％,AP221为54％。AR36存在最佳使用浓度（200mg／L）;SP169、AP221脱水率随浓度的增加而增大。破乳剂浓度增加,可降低油水界面黏度,减弱界面膜强度,从而提高脱水效率。AR36脱水率随矿化度增加而增大,适用于高矿化度乳状液脱水;BP16921脱水率随矿化度增加而减小,不适合高矿化度乳状液脱水。其它4种破乳剂的脱水效率与矿化度无对应关系。     

Investigation of Kinetic and Rheological Properties for the Demulsification Process

Chemical demulsification process is the most widely applied method of treating water in crude oil emulsions and involves the use of chemical additives to accelerate the emulsion breaking process. Hence, five demulsifiers were prepared in two steps. In the first step, the nonyl phenol was polymerized with formaldehyde to obtain five different molecular weights polymers. In the second step, the resulting polymers were ethoxylated with 50 ethylene oxide units and propoxylated with 10 propylene oxide units, yielding (D₁–D₅). The demulsification efficiency of these demulsifiers was investigated. The influence of viscosity on the droplet diameter for water-in-crude oil emulsion with three different ratios; 30:70, 50:50 and 70:30 (v/v) w/o emulsions were examined. The results showed that, the viscosity of w/o emulsion was strongly augmented by increasing volume of water before reaching the inversion point. The yield point which is required to start the flow decreases with decreasing water percent. The coalescence rate increases with increasing drop size for D₅ as a representative sample. Results show that, the droplet size increases with increasing water content. The efficiency of water separation increases as the molecular weight increase.     

Optimum demulsifier formulations for Nigerian crude oil-water emulsions

The formation of crude emulsion during oil production and processing is a challenge of significant proportions to the oil producers. Studies show that about two third of Nigerian crude oil production is in form of water in oil emulsion. For economic and operational reasons, it is necessary to separate the water completely from the crude oil before transportation or refining.Efficiency of separation of crude emulsions is of major importance to producers. To this end, this study primarily seeks to investigate the formulation of effective demulsifier that can be used to achieve this aim; and in so doing, the optimal separation efficiency attainable by this demulsification process is determined. Six different samples of water and oil soluble demulsifiers were used on two different samples of synthetic emulsion (sample I and II (both water in oil emulsion) from different Nigerian oil fields). The bottle test method was used to determine the percentage water separation for each crude oil emulsion/chemicals (demulsifiers) mixture. The concentrations of the combined six chemicals (demulsifier samples A–F) in the mixture were related to the percentage water separation using response surface methodology central composite design (RSMCCD).Results show that the optimum concentrations of demulsifiers A–F are 59?ppm/39?ppm/29?ppm/20?ppm/29?ppm/13?ppm respectively for crude oil sample I. While 54?ppm/40?ppm/25?ppm/21?ppm/29?ppm/8?ppm respectively were observed as optimum concentration for crude oil II. The combination of these chemical was observed to return better performance than the existing commercial demulsifiers with percentage water separation of 92% and 94% compared to percentage water separation of 87% and 90% returned by one of the currently available demulsifier used in the petroleum industry for crude oil A and B respectively. Hence, the need to carry out optimization analyses on different emulsified crude oil cannot be over-emphasize.     

降压脱气对溶CO2原油乳液中水滴稳定性的影响

通过对CO₂在油/水/乳液中的溶解度、溶CO₂原油的流动性、溶CO₂后油-水间的界面特性、溶CO₂原油乳液的稳定性、油-水界面压力变化的测试与计算,分析溶CO₂原油乳液在降压脱气过程中水滴稳定性的变化规律。结果表明：溶CO2原油乳液中,沥青质等界面活性物质能够迅速地迁移并吸附于油-水界面,并微弱提高油相对CO₂的溶解能力,并使得油-水界面张力快速降低,界面弹性模量增大,降低界面扩张损耗角;溶入CO₂能够降低油相黏度,提高水滴沉降速率,使得原油乳液的分油率增大;降压脱气时,水相中CO₂气泡的析出、长大,迫使水滴膨胀,降低界面上活性物质的浓度,减小了油-水界面压力,使得水滴的聚结稳定性变差,增大了原油乳液的分水率。     

非聚醚型破乳剂的破乳效果

以丙烯酸、甲基丙烯酸、丙烯酸丁酯、甲基丙烯酸甲酯、苯乙烯等为原料,在胶束水溶液中合成了一系列非聚醚型破乳剂.采用试瓶法对模拟采出原油乳状液进行了破乳实验研究.结果表明,含有亲水性基团的非聚醚型破乳剂,由于分子结构的双亲性,有利降低油水界面膜强度和增加动态界面活性,使其破乳效果优于油溶性破乳剂的破乳效果,但过强的亲水性会...     

高分子表面活性剂驱采出液破乳剂的研制和现场试验

针对大庆油田高分子表面活性剂驱试验井的采出液,合成了系列原油破乳剂。在大庆油田采油现场对6种破乳剂进行了试验评价,研究了油基破乳剂和水基破乳剂的配伍性,探讨了加药方式对破乳效果的影响。试验结果表明：单独使用油基破乳剂或水基破乳剂皆不能达到现场生产要求;油基破乳剂YJ01与水基破乳剂具有良好的配伍性,油基破乳剂YJ02与水基破乳剂不配伍;采用先加入油基破乳剂YJ01,5min后再加入水基破乳剂SJ02的加药方式能取得良好的破乳效果,破乳后油相含水率与水相含油率皆达到现场生产指标要求。     

Reduction of the Total Acid Number of Crude Oil with Basic Solution

Reduction of total acid number (TAN) of crude oil with sodium hydroxide and sodium carbonate solution was investigated. For emulsion emerging in an acid removal process by a sodium hydroxide solution, effects of the volume ratio of sodium hydroxide solution to crude oil and dosage of demulsifiers have been investigated. A model has been engaged to explain the interfacial behavior. When the volume ratio of sodium hydroxide solution (4 wt%) to crude oil exceeds 2, the formed emulsion is an unstable oil-in-water emulsion. When the volume ratio of 4 wt% sodium hydroxide to crude oil reaches 4:1, the total dosage of demulsifiers is 20 mg/l, the weight ratio of non-ion demulsifier LA42 to cationic demulsifier LGA is 1:1, the temperature reaches 40°C, most naphthenic acids were removed from crude oil and the emulsion separated quickly.     

The Demulsification of Crude Emulsion of ASP Flooding by an Organic Silicone Demulsifier

Abstract

In order to enhance crude oil recovery, the dosages of alkali, surfactant, and polymer in the tertiary flooding are becoming increasingly higher, which makes the emulsion more difficult to demulsify. In this article the application of new organic silicone demulsifiers for the demulsification of produced crude emulsion of alkali-surfactant-polymer (ASP) flooding with higher concentrations of alkali, surfactant, and polymer was investigated. The result indicated that organic silicone demulsifiers whose hydrophile–lipophile balance (HLB) number ranged from 10 to 15 had a satisfactory effect on demulsification. The dewatering efficiency can be improved evidently by adding a demulsifier mixed with DC2 and JG31 whose volume ratio was 4:1. The dewatering efficiency for produced crude emulsion from ASP flooding could exceed 80% at 60°C in which the concentrations of alkali, polymer, and surfactant ranged from 1,200 to 9,000 mg/L, 400 to 1,000 mg/L, and 200 to 800 mg/L, respectively. The simulative industrialized experiment of the ASP flooding produced emulsion was made, the dewatering efficiency was 99.6%, and the oil content of the produced water was less than 100 mg/L.     

海上油田酸化返排液对原油脱水性能的影响

埕岛油田重要的增产工艺措施是酸化作业,酸化返排液直接进入集输系统会造成破乳剂等常规处理药剂效果变差或失效。为了确定酸化返排液的乳化机理,对不同返排时间的返排液进行物性分析,并结合分析结果进行了各组分对原油乳化稳定性及破乳效果的影响实验,为了评价酸化过程中各组分对原油乳状液稳定性影响的重要程度,采用正交实验法耦合pH值、浊度和铁离子浓度3个因素,选择脱水率较高的水平范围通过正交表确定实验方案,进行三种因素共同作用下对原油脱水性能实验。通过脱水率的极差分析与方差分析,确定浊度为原油乳状液破乳的主要影响因素,为有效处理酸化返排液,可采用深度过滤工艺控制返排液中悬浮固体含量,有助于稳定原油脱水系统并提高油井生产时率。